A number of standards have been promulgated with relation to the Third Generation Partnership Project (3GPP), including specifications related to wideband CDMA. One aspect of wideband CDMA involves the downlink scrambling code, or “Gold code”. The downlink scrambling code is used to assist in differentiating between multiple base stations and multiple logic channels, as well as assisting in timing synchronization and other aspects.
In 3GPP wideband CDMA, the downlink scrambling code is generated by a scrambling code sequence generator. Scrambling code generators are replicated throughout a wideband CDMA network to perform various aspects as described above. A scrambling code generator includes two linear feedback shift registers (LFSRs), often referred to as the x and y LFSRs. The x and y LFSRs produce the downlink scrambling code based on a specific set of initial states and output masks. At the end of each radio frame (i.e., 38400 chips or samples), the scrambling code sequence generator is reset and the output sequence is repeated. The scrambling code may be generated from any arbitrary point in the frame, as opposed to the frame boundary, by using an appropriate set of x and y initial states, or an equivalently appropriate set of x and y masks.